Sensing and feedback for row on sun tracking method and system

ABSTRACT

A solar tracker system comprising a plurality of on sun trackers and a plurality of off sun tracker. Each tracker is selectively adjusted to achieve a desired power output of the solar power plant system in an example.

CROSS-REFERENCE TO RELATED APPLICATIONS

This present application is a continuation of U.S. patent applicationSer. No. 16/788,171 filed Feb. 11, 2020, which is a continuation of U.S.patent application Ser. No. 15/645,989 filed Jul. 10, 2017, now U.S.Pat. No. 10,557,646, which claims priority to U.S. Provisional Nos.62/360,857 filed Jul. 11, 2016, 62/419,383 filed Nov. 8, 2016,62/419,386 filed Nov. 8, 2016, and 62/492,870 filed May 1, 2017, each ofwhich is incorporated by reference in its entirety.

BACKGROUND

The present application relates generally to a tracking system for solarpanels. More specifically, embodiments of the present invention providetracking systems that are suitable for solar panels. In a specificembodiment, a tracking system according to the present invention isfully configurable in relation to each other, among other aspects. Thereare other embodiments as well.

As the population of the world increases, industrial expansion has leadto an equally large consumption of energy. Energy often comes fromfossil fuels, including coal and oil, hydroelectric plants, nuclearsources, and others. As an example, the International Energy Agencyprojects further increases in oil consumption, with developing nationssuch as China and India accounting for most of the increase. Almostevery element of our daily lives depends, in part, on oil, which isbecoming increasingly scarce. As time further progresses, an era of“cheap” and plentiful oil is coming to an end. Accordingly, other andalternative sources of energy have been developed.

Concurrent with oil, we have also relied upon other very useful sourcesof energy such as hydroelectric, nuclear, and the like to provide ourelectricity needs. As an example, most of our conventional electricityrequirements for home and business use come from turbines run on coal orother forms of fossil fuel, nuclear power generation plants, andhydroelectric plants, as well as other forms of renewable energy. Oftentimes, home and business use of electrical power has been stable andwidespread.

Most importantly, much if not all of the useful energy found on theEarth comes from our sun. Generally, all common plant life on the Earthachieves life using photosynthesis processes from sun light. Fossilfuels such as oil were also developed from biological materials derivedfrom energy associated with the sun. For human beings including “sunworshipers,” sunlight has been essential. For life on the planet Earth,the sun has been our most important energy source and fuel for modernday solar energy.

Solar energy possesses many characteristics that are very desirable!Solar energy is renewable, clean, abundant, and often widespread.Certain technologies have been developed to capture solar energy,concentrate it, store it, and convert it into other useful forms ofenergy.

Solar panels have been developed to convert sunlight into energy. As anexample, solar thermal panels often convert electromagnetic radiationfrom the sun into thermal energy for heating homes, running certainindustrial processes, or driving high grade turbines to generateelectricity. As another example, solar photovoltaic panels convertsunlight directly into electricity for a variety of applications. Solarpanels are generally composed of an array of solar cells, which areinterconnected to each other. The cells are often arranged in seriesand/or parallel groups of cells in series. Accordingly, solar panelshave great potential to benefit our nation, security, and human users.They can even diversify our energy requirements and reduce the world'sdependence on oil and other potentially detrimental sources of energy.

Although solar panels have been used successfully for certainapplications, there are still limitations. Often, solar panels areunable to convert energy at their full potential due to the fact thatthe sun is often at an angle that is not optimum for the solar cells toreceive solar energy. In the past, various types of conventional solartracking mechanisms have been developed. Unfortunately, conventionalsolar tracking techniques are often inadequate. These and otherlimitations are described throughout the present specification and maybe described in more detail below.

From the above, it is seen that techniques for improving solar systemsare highly desirable.

SUMMARY OF THE INVENTION

The present application relates generally to a tracking system for solarpanels. More specifically, embodiments of the present invention providetracking systems that are suitable for solar panels. In a specificembodiment, a tracking system according to the present invention isfully configurable in relation to each other, using sensing and feedbackdevices, among other aspects. There are other embodiments as well.

In an example, the present invention provides a tracker system. Thesystem has a first tracker apparatus comprising a first row of aplurality of solar modules, each of the solar modules being spatiallyconfigured to face in a normal manner in an on sun position in anincident direction of electromagnetic radiation derived from the sun;and a second tracker apparatus comprising second row of a plurality ofsolar modules, each of which is configured in an off sun direction suchthat each of the solar modules does not block and shade any one of theplurality of solar modules from the first row.

In an example, the system has an optimized power output. The system alsohas the first solar tracker apparatus is one of a plurality of on suntracker apparatuses. The system has the second solar tracker apparatusis one of a plurality of off sun tracker apparatuses. In an example,each of the solar trackers in the off sun position is adjacent to a pairof trackers in an off sun position.

In an example, a measuring device will on each row will identify when arow starts to become shaded and it will be recorded by the system. In anexample, the system uses row to row information to optimize a trackingangle based on local conditions, such as, for example, sloping hills andchanging ground cover ratios or other non-uniformities. In an example,the system will optimize for shading that my only be from East or West(morning or evening), although there can be other variations. In anexample, each module can also the measuring device.

In an example, the present invention provides a solar power plantsystem. The system has a plurality of solar tracker apparatus, each ofthe solar tracker apparatus having a plurality of solar modules. Thesystem has a controller device coupled to each of tracker apparatus, atleast one drive device coupled to each of the tracker apparatus andoperably coupled to the controller device, and optionally, a solar powerstrip coupled to the controller device, and provided to generate supplypower to the controller device and the drive device. In an example, thesolar power strip has a width of about 1/10^(th) or more of a length ofthe solar power strip. In an example, the solar power strip isconfigured between a pair of solar modules in each of the trackerapparatus. The system has a network interface coupled to each of thecontroller devices, and a main controller device coupled to each of thecontroller devices using the network interface. The system has a widearea network connection coupled to the main controller device, andcoupled to an external weather forecasting source using the wide areanetwork, a plant control module stored in a memory device coupled to themain controller device, a first data source for information regardingdetailed site geometry comprising a three coordinate information, and asecond data source for the external weather forecasting source andcoupled to the wide area network. The system has an irradiance sensorcoupled main controller device, the irradiance sensor being configuredwith the system to capture at least local weather information for adesired time period in association with the solar power plant system.

In further examples, the present method and system can be illustratedusing the following examples.

Sloping hill with morning versus evening. In an example, illustrationscan be found first with shading, then corrected angle without shading.

Different ground cover ratio with morning versus evening. In an example,illustrations can be found first with shading, then corrected anglewithout shading.

In other illustrations, a measuring device as a narrow module thatextends past standard modules is provided. In an example, acceptableshading of narrow module where tips are shaded, are included. In anexample, non-acceptable shading of narrow module where shading thenreaches to the standard module is included. Further details of the solartracker system are described throughout the present specification andmore particularly below.

Various additional objects, features and advantages of the presentinvention can be more fully appreciated with reference to the detaileddescription and accompanying drawings that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 through 22 illustrate a plurality of tracking systems configuredfor row on sun, using differing tracker positions configured withsensing and feedback devices, according to an embodiment of the presentinvention.

FIG. 23 through 35 illustrate a solar power strip and relatedinformation according to an embodiment of the present invention.

FIG. 36 is a simplified diagram of a solar power plant according to anembodiment of the present invention.

FIG. 37 is a simplified block diagram of a capture control module forthe solar power plant according to an embodiment of the presentinvention.

FIG. 38 is a simplified diagram illustrating a method of using the solarpower plant according to an embodiment of the present invention.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

The present application relates generally to a tracking system for solarpanels. More specifically, embodiments of the present invention providetracking systems that are suitable for solar panels. There are otherembodiments as well. Further details of the energy storage unit aredescribed throughout the present specification and more particularlybelow. Such energy storage unit can be configured with a self-poweredsolar tracker, as described.

In a specific embodiment, the present disclosure provides a trackerapparatus for solar modules. The tracker apparatus has a first pierincluding a first hanger assembly and a second pier including a driveassembly including a drive mount. The drive mount is capable ofcompensating for construction tolerances in at least three axes and isconfigured to a drive device. The drive device has an off-set clampdevice coupled to a cylindrical bearing device coupled to a clamphousing member. The tracker apparatus has a cylindrical torque tubeoperably disposed on the first pier and the second pier. The cylindricaltorque tube includes a first end and a second end, and a notch. Thenotch is one of a plurality of notches spatially disposed along a lengthof the cylindrical torque tube. The tracker apparatus has a clampconfigured around an annular portion of the cylindrical torque tube andmate with the notch to prevent movement of the clamp. The clamp includesa support region configured to support a portion of a solar module.

In an example, the self-powered solar tracker apparatus has a drivedevice. The apparatus has a crank coupled to the drive device andconfigured in an offset manner to a first end of a continuous torquetube, which has a plurality of torque tubes, each of the torque tubesbeing cylindrical in shape. In example, the apparatus has a frameassembly coupled to the continuous torque tube. In an example, the frameassembly coupled to a plurality of solar modules. In an example, theapparatus has a clamp assembly comprising a housing configured to becoupled to a second end of the continuous torque tube such that thecontinuous torque tube is suspended from the housing. In an example, thehousing comprises an opening having a major plane normal to a length ofthe continuous torque tube. In an example, the opening comprises a firstinner region and a second inner region, the first inner region acts as afirst stop for the continuous torque tube when moved in a first radialdirection until contact with the first inner region, and the secondinner region acts as a second stop for the continuous torque tube whenmoved in a second radial direction until contact with the second innerregion. In an example, the drive motor is operable to move the torquetube about a center of rotation and is substantially free from a loadand moves the torque tube about the center of rotation at substantiallya same force from a first radial position to a second radial position.In an example, the center of rotation is offset from a center of thecontinuous torque tube via the crank configured in the offset manner.Further details are provided throughout the present specification andmore particularly below.

In an alternative embodiment, the present disclosure provides analternative solar tracker apparatus. The tracker apparatus has a drivedevice, a crank coupled to the drive device and configured in an offsetmanner to a frame assembly. The frame assembly is coupled to a pluralityof solar modules.

In an embodiment, the tracker apparatus has a continuous torque tubespatially disposed from a first region to a second region. The crankincludes a first crank coupled to a first side of the drive device and asecond crank coupled to a second side of the drive device. A firsttorque tube is coupled to the first crank and a second torque tube iscoupled to the second crank. A first swage fitting couples the firstcrank to the first torque tube and a second swage fitting couples thesecond crank to the second torque tube. The tracker apparatus also has asecond pier coupled to the drive device. In an embodiment, the trackerapparatus also has a drive mount coupled to the second pier.

In an alternative embodiment, the present disclosure provides analternative solar tracker apparatus. The tracker apparatus has anadjustable hanger assembly aligned with a center of mass and configuredwith a clam shell clamp housing member assembly on the adjustable hangerassembly and a cylindrical torque tube including a plurality of torquetubes configured together in a continuous length from a first end to asecond end such that the center of mass is aligned with a center ofrotation of the cylindrical torque tubes to reduce a load of a drivemotor operably coupled to the cylindrical torque tube.

In an embodiment, the drive motor is operable to move the torque tubeabout the center of rotation and is substantially free from a load. Thecenter of rotation is offset from a center of the cylindrical torquetube.

In an alternative embodiment, the present disclosure provides a solartracker apparatus. The tracker apparatus has a clamp housing memberconfigured in an upright direction. The clamp housing member includes alower region and an upper region. The lower region is coupled to a pierstructure, and the upper region includes a spherical bearing device. Theupright direction is away from a direction of gravity. The trackerapparatus has a clam shell clamp housing member coupled to the sphericalbearing and a torque tube coupled to the spherical bearing device tosupport the torque tube from the upper region of the clamp housingmember. The torque tube is configured in an off-set position from acenter region of rotation.

In an embodiment, the tracker apparatus is configured substantially freefrom any welds during assembly. Reduced welding lowers cost, improvesinstallation time, avoids errors in installation, improvesmanufacturability, and reduces component count through standardizedparts. The torque tube is coupled to another torque tube via a swagedevice within a vicinity of the clam shell clamp housing member. In anembodiment, the connection is low cost, and provides for strong axialand torsional loading. The tracker apparatus is quick to install withthe pokey-yoke design.

The torque tube is coupled to an elastomeric damper in line to dampentorque movement to be substantially free from formation of a harmonicwaveform along any portion of a plurality of solar panels configured tothe torque tube. The tracker apparatus also has a locking damper orrigid structure to configure a solar panel coupled to the torque tube ina fixed tilt position to prevent damage by securing the solar panel in aposition that is substantially free from fluttering in an environmentwith high movement of air.

The tracker apparatus further includes a controller tracker apparatusconfigured in an inverter box provided in an underground region toprotect the controller tracker apparatus. The tracker apparatus has adrive device to linearly actuate the torque tube. In an embodiment, thetracker apparatus uses an electrical connection coupled to a drivedevice.

In an embodiment, the spherical bearing device allows for accommodationof a construction tolerance, tracker movement, and acts as a bondingpath of least resistance for taking an electrical current to ground.

The tracker apparatus can be one of a plurality of tracker apparatusconfigured in an array within a geographic region. Each of the pluralityof tracker apparatus is driven independently of each other to cause eachrow to stow independently at a different or similar angle.

Still further, the present disclosure provides a tracker apparatusincluding a clam shell clamp, which has a first member operably coupledto a second member to hold a torque tube in place.

In an embodiment, the tracker apparatus also has a clamp housing memberoperably coupled to the clam shell clamp via a spherical bearing devicesuch that the spherical bearing device includes an axis of rotation. Theaxis of rotation is different from a center of the torque tube. Thetracker apparatus further includes a solar module coupled to the torquetube.

In an embodiment, the disclosure provides a tracker apparatus includinga plurality of torque tubes including a first torque tube coupled to asecond torque tube coupled to an Nth torque tube, wherein N is aninteger greater than 2. Each pair of torque tubes is coupled to eachother free from any welds.

In an embodiment, each pair of torque tubes is swage-fitted together.Each of the torque tubes is cylindrical in shape. Each of the pluralityof torque tubes is characterized by a length greater than 80 meters.Each of the torque tubes includes a plurality of notches. In anembodiment, the tracker apparatus also has a plurality of U-bolt devicescoupled respectively to the plurality of notches. Each of the pluralityof torque tubes are made of steel.

In an alternative embodiment, the present disclosure provides a trackerapparatus having a pier member including a lower region and an upperregion. A clamp holding member is configured to the upper region and iscapable of moving in at least a first direction, a second directionopposite to the first direction, a third direction normal to the firstdirection and the second direction, a fourth direction opposite to thethird direction, a fifth direction normal to the first direction, thesecond direction, the third direction, and the fourth direction, and asixth direction opposite to the fifth direction.

In yet an alternative embodiment, the present disclosure provides asolar tracker apparatus. The tracker apparatus has a clamp housingmember configured in an upright direction. The clamp housing memberincludes a lower region and an upper region. The lower region is coupledto a pier structure. The upper region includes a spherical bearingdevice. The upright direction is away from a direction of gravity. Thetracker apparatus has a clam shell clamp housing member coupled to thespherical bearing and the clam shell clamp housing member beingsuspended from the spherical bearing. In an example, the bearing canalso by cylindrical, or fixed within a support structure, which allowsthe torque tube to hang freely. In an embodiment, the tracker apparatushas a torque tube including a first end and a second end. The first endis coupled to the spherical bearing device to support the torque tubefrom the upper region of the clamp housing member. The torque tube isconfigured in an off-set position from a center region of rotation. Thetracker apparatus has a drive device coupled to the second end such thatthe drive device and the torque tube are configured to be substantiallyfree from a twisting action while under a load, e.g., rotation, wind,other internal or external forces.

In an embodiment, the present disclosure provides a solar trackerapparatus. In an embodiment, the tracker apparatus includes anadjustable hanger assembly aligned with a center of mass and configuredwith a clam shell clamp housing member assembly on the adjustable hangerassembly and a cylindrical torque tube including a plurality of torquetubes configured together in a continuous length from a first end to asecond end such that the center of mass is aligned with a center ofrotation of the cylindrical torque tubes to reduce a load of a drivemotor operably coupled to the cylindrical torque tube. Further detailsof the present example, among others, can be found throughout thepresent specification and more particularly below.

In an example, the present invention provides a solar tracker systemconfigured with an energy storage unit. The system has a trackerapparatus, comprising a torque tube extending from a first end to asecond end. The system has at least a pair of pillars supporting alength of the torque tube, and a plurality of solar panels disposedspatially along the torque tube from the first end to the second end,each of the plurality of solar panels having an aperture region and abackside region. The system has an energy storage unit spatiallydisposed between the pair of pillars, and underlying the backside regionof each of the plurality of trackers, the energy storage unit comprisingan anode, a cathode, and an electrolyte disposed between the anode andthe cathode. The system has a first output terminal coupled to theanode; and a second output terminal coupled to the cathode and a voltagedefined between the first output terminal and the second outputterminal. The system has an inverter device coupled to the first outputterminal and the second output terminal, the inverter device beingcapable of converting a DC input into an AC output. The system has awidth of about 1.5 feet, a height of about 1.5 feet, and a length ofabout 20 feet about 30 feet characterizing a volume of the energystorage unit. The system also has a controller device coupled to thetracker apparatus, the energy storage unit, and the inverter device, anda power grid; the controller device comprising an input power terminal,the input power terminal being coupled to the energy storage unit.

In an example, the electrolyte comprises a liquid material, the liquidmaterial. In an example, the electrolyte comprises a lithium bearingmaterial. In an example, the inverter device comprises a DC to ACmicro-inverter. In an example, the controller device is coupled to amain controller. In an example, the energy storage unit comprises aplurality of battery units. In an example, the tracker apparatus isfixed or movable tracker. In an example, the controller device iscoupled to the energy storage device using the inverter device toprovide an input voltage of 24 volt DC. Further details of the presentexample, among others, can be found throughout the present specificationand more particularly below.

As shown, the present disclosure provides a tracker apparatus for solarmodules, and energy storage unit. In an embodiment, the solar modulescan be a silicon based solar module, a poly silicon based solar module,a concentrated solar module, or a thin film solar module, includingcadmium telluride (CdTe), copper indium gallium selenide(CuIn_(1-x)Ga_(x)Se₂ or CIGS), which is a direct bandgap semiconductoruseful for the manufacture of solar cells, among others. As shown, eachof the solar panels can be arranged in pairs, which form an array. Ofcourse, there can be other variations. In an embodiment, the first pierand the second pier are provided on a sloped surface, an irregularsurface, or a flat surface. A first pier and a second pier are two of aplurality of piers provided for the tracker apparatus 100. In example,the tracker apparatus has a solar module held in a hanging position or asupporting position.

The tracker apparatus has a first pier including a first hanger assemblyand a second pier including a drive assembly. In an embodiment, thefirst pier is made of a solid or patterned metal structure, such as awide beam flange or the like, as shown. In an embodiment, each of thepiers is inserted into the ground, and sealed, using cement or otherattachment material. Each pier is provided in generally an uprightposition and in the direction of gravity, although there can bevariations. In an embodiment, each of the piers is spatially spacedalong a region of the ground, which may be flat or along a hillside orother structure, according to an embodiment. In an embodiment, the firstpier includes a wide flange beam. In an embodiment, the first pier andthe second pier can be off-set and reconfigurable.

In an embodiment, the drive assembly is capable for constructiontolerances in at least three axes and includes a drive mount that isconfigured to a drive device. The drive device has an off-set clampdevice coupled to a cylindrical bearing device coupled to a clamphousing member.

In an embodiment, the tracker apparatus has a cylindrical torque tubeoperably disposed on the first pier and the second pier. In anembodiment, the cylindrical torque tube includes a one to ten-inchdiameter pipe made of Hollow Structure Steel (HSS) steel. Thecylindrical torque tube includes a first end and a second end, and anotch. The notch is one of a plurality of notches spatially disposedalong a length of the cylindrical torque tube.

In an embodiment, the tracker apparatus has a clamp configured around anannular portion of the cylindrical torque tube. The clamp mates with thenotch to prevent movement of the clamp. The clamp includes a supportregion configured to support a portion of a solar module. The clampincludes a pin configured with the notch. The tracker apparatus also hasa rail configured to the clamp. The rail includes a thread regionconfigured to hold a bolt, which is adapted to screw into the thread andbottom out against a portion of cylindrical torque tube such that theclamp is desirably torqued against the cylindrical torque tube. Thetracker apparatus has a solar module attached to the rail or otherattachment device-shared module claim or other devices. The cylindricaltorque tube is one of a plurality of torque tubes configured in as acontinuous structure and extends in length for 80 to 200 meters. Eachpair of torque tubes is swage fitted together and bolted for theconfiguration.

In an embodiment, the tracker apparatus also has a center of mass alongan axial direction that is matched with a pivot point of the drivedevice. The pivot point of the drive device is fixed in three dimensionswhile rotating along the center of mass. In an embodiment, the off-setclamp includes a crank device. The first hanger assembly includes aspherical bearing device configured a clam-shell clamp device to securethe first end to the cylindrical torque tube. In other examples, thedrive device includes a slew gear. The tracker apparatus also has anoverrun device configured with the first hanger assembly. The overrundevice includes a mechanical stop to allow the cylindrical torque tubeto rotate about a desired range.

FIGS. 1 through 22 illustrate a plurality of tracking systems configuredfor row on sun, using differing tracker positions, and a measuringdevice, according to an embodiment of the present invention. As shown,the system has a plurality of trackers, each of which is configured in aterrain having an uneven slope, as shown in FIG. 1. In an example, eachof the trackers is tuned taking into consideration shading influencesfrom adjacent trackers, geological terrain, weather, including local andglobal, time of day, and other influences, which will be described morefully below.

In an example, the tracker system has at least a first tracker apparatuscomprising a first row of a plurality of solar modules. In an example,each of the solar modules is spatially configured to face in a normalmanner in an on sun position in an incident direction of electromagneticradiation derived from the sun. The system has a second trackerapparatus having a second row of a plurality of solar modules. In anexample, each of the solar modules is configured in an off sun directionsuch that each of the solar modules does not block and shade any one ofthe plurality of solar modules from the first row using feedback from ameasuring device coupled to second tracker device.

In an example, the first solar tracker apparatus is one of a pluralityof on sun tracker apparatuses. In an example, the second solar trackerapparatus is one of a plurality of off sun tracker apparatuses. Each ofthe solar trackers is in the off-sun position is adjacent to a pair oftrackers in an on sun position in an example, but can be in otherconfigurations to achieve a desired power output of the solar plant.

In an example, the solar power plant also has a method of using a solarsystem. The method includes using a solar power plant system comprisinga first tracker apparatus comprising a first row of a plurality of solarmodules. In an example, each of the solar modules is spatiallyconfigured to face in a normal manner in an on sun position in anincident direction of electromagnetic radiation derived from the sun. Inan example, the system has a second tracker apparatus comprising asecond row of a plurality of solar modules. In an example, each of theplurality of solar modules is configured in an off sun direction suchthat each of the solar modules does not block and shade any one of theplurality of solar modules from the first row. In an example, the methodincludes using a measuring device coupled to the second trackerapparatus to provide feedback to the system or second tracker to achievea desired power output of the solar plant. A perspective view diagram ofa solar tracker is shown in FIG. 2. A more detailed diagram of a solartracker is shown in FIG. 3, and a further detailed diagram is shown inFIGS. 4 and 5. A solar panel for generating power for the individualtracker is shown in each of FIGS. 4 and 5, and a sensor for sensingirradiance from the sun is also shown in each of these Figures. FIGS. 6to 9 illustrate various top view diagrams of the solar tracker, whileFIGS. 10 to 12 show various side view diagrams of the solar tracker.FIGS. 13 to 17 illustrate various views of an irradiance-sensing device,which is coupled to the solar tracker according to an example. FIGS. 18to 22 illustrate various views of a narrowed solar panel configured as asensing device, which is coupled to the solar tracker according to anexample. Further details of a solar power strip for generating power tocontrol and move the solar tracker according to an example are providedthroughout the present specification and more particularly below.

FIG. 23 through 36 illustrate a solar power strip and relatedinformation according to an embodiment of the present invention. In anexample, a proposed solution uses series connect one quarter (¼), onethird (⅓), or one half (½) size cells using conventional ribbon assemblytechnology.

FIG. 23 illustrates a solar power strip (or charging panel location)within each of the solar trackers. The trackers are arranged from Northto South, as shown, and allow the modules to traverse from East to West,also shown. Various experiments were performed using full cells (FIG.24), one-third cells in series connection (FIG. 25), and one half cellsin series connection (FIG. 26).

In an example under another proposal, a solar power strip was designedand constructed with samples using one quarter (¼), one third (⅓), onehalf (½), size of solar cells using conventional ribbon assemblytechnology. In an example, each of the samples was tested using testmodule I-V characteristics under shaded conditions. Additionally, eachof the modules was tested using the test module and controller on thetracker on site in an example. The design included vertical andhorizontal layups, See FIGS. 27 and 28.

FIG. 29 illustrates examples of ½ cell, ⅓ cell, and ¼ cell designs.Various tests were performed on ½ cut cells (FIG. 30), ⅓ cut cells (FIG.31), and ¼ cut cells (FIG. 32). Additional data is shown in FIG. 33 andFIG. 34 for each of the designs. FIG. 35 illustrates a 60 W power stripwith ¼ cut cells in an example. FIG. 35 illustrates a 110 W power stripwith ½ cut cells in an example. These power strips can be used togenerate power to the tracker for its movement, and control according toan example. Further details of the present power strip as configuredwith the solar tracker are described throughout the presentspecification and more particularly below.

FIG. 36 is a simplified diagram of a solar power plant according to anembodiment of the present invention. As shown is a solar power plantsystem. The system has a plurality of solar tracker apparatus arrangedin parallel to each other in an example. Each of the solar trackerapparatus has a plurality of solar modules arranged from North to South,and traverses from East to West. In an example, each tracker has acontroller device (SPC) coupled to each of tracker apparatus. As anexample, the controller can be any micro controller based system, microprocessor based system, or other processor including suitable memory anda communication interface. In an example, at least one drive devicecoupled to each of the tracker apparatus and operably coupled to thecontroller device. Further details of the drive device can be found inany of co-pending cases related to U.S. Pat. No. 9,905,7171 filed Dec.9, 2013, which claims priority to U.S. Provisional Application No.61/735,537 filed Dec. 10, 2012 (originally Attorney Docket No.906RO-017400US), each of which is incorporated by reference herein forall purposes. The present application also incorporates by reference,for all purposes, the following concurrently filed patent applications,all commonly owned: U.S. Pat. No. 9,766,319 entitled OFF-SET DRIVEASSEMBLY FOR SOLAR TRACKER, filed Sep. 17, 2014, and U.S. Pat. No.10,008,975 entitled CLAMP ASSEMBLY FOR SOLAR TRACKER, filed Sep. 17,2014.

In an example, each tracker also has a solar power strip coupled to thecontroller device, and provided to generate supply power to thecontroller device and the drive device. In an example, the solar powerstrip has a width of about 1/10th or more of a length of the solar powerstrip. In an example, the solar power strip is configured between a pairof solar modules in each of the tracker apparatus, as described earlier,in an example.

In an example, a network interface coupled to each of the controllerdevices. The network interface can be a WiFi, Bluetooth, or otherwireless network, meshed network, or other configuration, amongcombinations there. In an example, a system controller device is coupledto each of the controller devices using the network interface (NCU-1),an example. The controller also has main controller, switch, andwireless communication interface device, as shown.

The system controller also communicates to a wide area networkconnection coupled to the main controller device, and coupled to anexternal weather forecasting source using the wide area network. Thewide area network configuration includes switch, local client,modem/router, Internet, and remote client, which can be a smart phone,laptop, tablet, or other computing devices. The system controller isalso a plant control module stored in a memory device coupled to themain controller device.

In an example, the system is also coupled to a first data source forinformation regarding detailed site geometry comprising a threecoordinate information and a second data source for the external weatherforecasting source (Weather Station) and coupled to the wide areanetwork. Each of these data sources will be described in further detailbelow, and the terms “first” and “second” or other number does notnecessarily imply order or logic. In an example, the system also has anirradiance sensor coupled main controller device. In an example, theirradiance sensor is configured with the system to capture at leastlocal weather information for a desired time period in association withthe solar power plant system. Power output of the solar power plant iscoupled to Distribution Panel, which is coupled to Utility Meter, andGrid, where Local Meter is between the Panel and Meter and communicatesto the system controller, as shown. Of course, there can be othervariations, modifications, and alternatives.

In a preferred embodiment, the system has a capture control module, thecapture control module being configured to generate off-set data, usinglocal weather information, information regarding detailed site geometry,and the external weather forecasting source, for each of the trackerapparatus in the solar power plant system. In an example, theinformation regarding the detailed site geometry is provided by a lasersite survey or other desired technique. In an example, the informationregarding the detailed site geometry is image data, such as satelliteimage, or other visual image. In an example, the external weatherforecasting information is provided using a sampling frequency of tenminutes, one hour, or one week. In an example, the information for thedetailed site geometry is tuned once, external weather forecast is tunedhourly, and monitoring weather information is performed at another. Inan example, the system is moving less to maximize energy output withdiffuse sunlight or does not move at all to maximize energy output to adesirable level. In an example, the main controller device comprises amain memory, a processor coupled to the main memory on a bus structure,and a capture control module coupled to the processor. Further detailsof the capture control module are found throughout the presentspecification and more particularly below.

In an example referring to FIG. 37, the capture control module iscoupled to main controller device and provided on a storage devicecoupled to the main controller device. The capture control module has anoutput coupled to each of the controller devices (Tracker ControllerDevice, shown in FIG. 37). In an example, the module has an inputcoupled to a local solar data source, e.g., Local Solar Data MeasurementDevice. The module has a recording module (Local Solar Data Storage andManagement Module) coupled to the input to transmit information relatedto the local solar data to external forecast service (External WeatherForecast Station). In an example, the external forecast serviceconfigured to generate a local data forecast to transmit back to thecapture control module to the Weather Forecast Lookup Module, as shown.The information is fed into a look-up table (DFI look up module) thathas historical information correlating tracker angles with energy outputfor a given local data forecast in an example. From the DFI look upmodule, information is transferred to an angle adjustment module(Diffuse Angle Adjustment Module) coupled to the look-up table and atopography module (Topography Execution, Topography Storage, andTopography Learning) comprising a learning module, storage module, andan execution module, as shown. In an example, the angle adjustmentmodule is configured to form a resulting angle adjustment or gain factorby processing information from the look-up table and the topographymodule to be transferred to an output handler. As shown, the outputhandler (Tracker Controller Gain Output Handler) is coupled to the angleadjustment module to output gain information to adjust each of thecontrollers coupled to each of the trackers. The Topography ExecutionModule transfers information to the Tracker Controller Parameter OutputHandler, as shown, which sends gain information to the TrackerController Device, which is coupled to each of the tracker apparatus.Further details of each of these blocks, which can be implemented inhardware, firmware, and software, or combinations thereof, can be foundbelow.

FIG. 37 is a simplified block diagram of a capture control module forthe solar power plant according to an embodiment of the presentinvention. In an example, the capture control module is implementedusing hardware, but can also be implemented using firmware, software, orany combination of hardware, firmware, and software. As shown, themodule has a local solar data measurement device. The local solarmeasurement device is a sensor that captures data on local solarirradiance. The sensor can be implemented using a solar panel, opticalsensor, thermal sensor, radiation sensor, or any combination of these.In an example, the sensor is provided in an irradiance meter to measurethe sun's energy, displaying the information in either W/m2 orBTU/hr-ft2 for the solar plant. In an example, the use of a photovoltaicreference cell provides a more representative measurement of solarenergy and greater accuracy and repeatability compared to irradiancemeters which use simple photo diode detectors. The local solar datameasurement device is used on the plant at the site to determine localconditions at the site. Of course, there can be other variations,modifications and alternatives.

In an example, the capture control module includes a local solar datastorage and management module, which receives real time information fromthe local solar data measurement device, as shown. Transmission of theinformation can occur via a hardwire, wireless, or other communicationtechnique. The local solar data storage and management module isimplemented in hardware, such as a memory device, that can be fixed,Flash, dynamic, or other forms of memory implemented in semiconductor orother electronic medium. In an example, the control module manages thecollection, validation, storage, and delivery of local solar data. Localsolar data is delivered to an external weather forecast service, usingan external wide area network connection, to provide a source of ‘groundtruth’ to improve and localize weather forecasts for the specificlatitude/longitude of the solar power plant, as shown. In an example,the capture control module has a weather forecast lookup module. Thelook up module queries the external weather forecast service to acquirelocal weather forecast for the solar power plant site.

In an example, a DFI lookup module is included. The diffuse fractionindex (DFI) lookup module contains a map that is learned on historicalweather data that has been processed through a power plant simulationmodule to determine the maximum energy output (or desired energy output)for a given tracker angle and weather condition. This map is used totransform weather forecasts into an adjustment angle, which will be usedto drive each of the given trackers.

The module also has a diffuse angle adjustment module. The diffuse angleadjustment module takes the raw diffuse angle adjustment and combines itwith the target tracker position to determine the correct trackercontroller gain factor. Also shown, and previously described, is anexternal weather forecast service that combines local solar data withone or more regional weather models to provide highly-localized (at thetracker site) weather forecasts suitable for the solar power plantlocation.

In an example, the module has a tracker controller gain output handler.The handler the delivery of individual gain factors to the trackercontrollers at every operational time-step. It manages and validatesgain factor delivery. The handler can be a software, firmware, or ahardware driver in an example.

The module has a topography-learning module. The topography learningmodule takes performance data from the tracker controllers fitted withspecialized combination sensor/generator photovoltaic panels andperforms computations using this performance data to determine solarpower plant topography. Additionally, a topography execution module isincluded. The capture control module uses the topography model stored inmemory and uses it to determine the correct individualized trackerparameters to deliver to each tracker controller device. In an example,the capture control module includes a tracker controller parameteroutput handler. The capture control module manages the delivery ofindividual parameter sets to the tracker controllers. It manages andvalidates parameter delivery. Additionally, a tracker controller deviceis included. The device controls an individual tracker. Each tracker isserved by a dedicated controller, which is also shown in the priorFigure. Accordingly, a plurality of controllers are coupled within solarpower plant. Topography storage module

This module stores and manages the learned topography of the solar powerplant. Depending upon the example, features of these modules can befurther separated, modified, combined, or implemented in other forms ofelectronic hardware and software. Further details of the presentinvention can be found throughout the present specification, and moreparticularly below.

FIG. 38 is a simplified diagram illustrating a method of using the solarpower plant according to an embodiment of the present invention. In anexample, the present method and related system includes various steps,as outlined in accordance to the Figure. In an example, the controllerdevice has an input for receiving a latitude information, a longitudeinformation, a time, as shown. In an example, a sun position modulecoupled to the input to calculate a sun position angle. The device has afirst gate device (decision block) coupled to the sun position moduleconfigured to determine whether to turn on (“No” branch) or turn off(“Yes” branch) an execution module in an example.

In an example, the system has an execution module being triggered froman initiation signal from the first gate device to capture informationto the East of a tracker and capture information to the West of thetracker to calculate an angle to determine a desired energy output fromthe tracker, as shown. In an example, the system has a backtrackingmodule configured to determine a shading avoidance position using thecaptured information using the time to determine an energy output, andusing an angle position to avoid shading if the energy output is greaterthan the desired energy output, and configured to use the desired energyoutput if the energy output is less than the desired energy output. Thesystem includes another gate device, as shown.

A second gate device is coupled to the capture control module to pollsfor information from the capture control module, and configured to usethe information if the information is available, using “Yes” branch, andpasses through to the “No” branch if information is not available. In anexample, another gate determines whether a certain diffused ratio (fordiffused sunlight) is achieved, which can also be part of the secondgate or a separate gate. If so, the system goes to a third gate, whileloops to move the tracker using the “No” branch. In an example, a thirdgate device (with “Yes” and “No” branches) is coupled to the second gatedevice to determine whether the main controller device has triggered theback tracking module, if the back tracking module has been triggeredthen using first angle information from the capture control module orusing second angle information from the capture control module, asshown. The system has an output for transferring either the first angleinformation or second angle information for the tracker to adjusts itsposition among the other trackers to output a desired level of power.

In an example, the system also has a pier height topography moduleprovided in the main controller. In an example, the pier heighttopography module is configured to gather shading information, usingeach of the solar power module strips, as each of the trackers traversefrom an initial position to a final position and from the final positionto the initial position to determine a pier height for each of thetracker apparatus, and a row sequencing for each of the trackerapparatus. In an example, pier height can be determined using thefollowing technique, which can be updated, modified, or combined:

Site Configuration Process

Set all rows to 60 degrees toward east in the morning till 10:00 am;

Relinquish the set-point lock and fall back to normal tracking;

Set all rows to 60 degrees toward west in the afternoon from 3:00 μm.

Data Acquisition

A voltage drop of solar power strip would be detected in a shadingevent.

Each row report back shading event instance to main controller.

Data Analysis

Based on the shading event time, site location, panel type, algorithmsare developed to estimate the row height difference of each tracker, aswell as the row sequencing (from east to west.) Of course, there can beother variations, modifications, and alternatives.

The present application relates to U.S. Pat. No. 9,905,7171 filed Dec.9, 2013, which claims the benefit of U.S. Provisional Application No.61/735,537 filed Dec. 10, 2012, each of which is incorporated byreference herein for all purposes. The present application also relatesto SELF-POWERED SOLAR TRACKER APPARATUS, in the names of Yang Liu andAlex Au and listed under U.S. Ser. No. 14/972,036 filed Dec. 16, 2015,which claims priority to U.S. Provisional Application No. 62/095,670,filed on Dec. 22, 2014, which is incorporated by reference herein in itsentirety.

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to persons skilled in the art and areto be included within the spirit and purview of this application andscope of the appended claims.

1. (canceled)
 2. A solar power plant comprising: a solar trackersupporting a plurality of solar modules; a drive device coupled to thesolar tracker and configured to rotate the solar tracker about an axis;a charging panel supported by the solar tracker and configured to powerthe drive device and to charge a battery supported by the solar tracker;and a controller in communication with a memory, the memory storingthereon instructions that when executed by the controller cause thecontroller to: receive forecast data for the solar power plant;determine, based on forecast data, a diffuse angle adjustment; andoutput a signal to the drive device to rotate the solar tracker to adesired angle based on the diffuse angle adjustment.
 3. The solar powerplant of claim 2, wherein the diffuse angle adjustment modifies a solartracker target angle based on a sun position angle.
 4. The solar powerplant of claim 3, wherein the diffuse angle adjustment is a gain factorapplied to the solar tracker target angle.
 5. The solar power plant ofclaim 3, wherein the controller further executes an instruction todetermine whether the solar tracker is in a backtracking mode.
 6. Thesolar power plant of claim 5, wherein when in a backtracking mode, thediffuse angle adjustment is a diffuse backtracking angle adjustment. 7.The solar power plant of claim 2, wherein the forecast data is receivedperiodically.
 8. The solar power plant of claim 2, wherein the memoryfurther stores a topography of the solar power plant.
 9. The solar powerplant of claim 8, further comprising a solar tracker target angle,wherein the solar tracker target angle is determined based on thetopography of the solar power plant.
 10. The solar power plant of claim2, further comprising a diffuse fraction index, wherein the diffusefraction index correlates the forecast data with a diffuse angleadjustment.
 11. The solar power plant of claim 10, wherein thecontroller applies the diffuse angle adjustment to modify a solartracker target angle for the solar tracker.
 12. The solar power plant ofclaim 11, wherein the solar tracker target angle is based on a sunposition angle and a topography of the solar power plant.
 13. The solarpower plant of claim 12, wherein the sun position angle is calculatedfrom a latitude and longitude of the solar tracker and a time of day.14. The solar power plant of claim 2, further comprising a local solarmeasurement device.
 15. The solar power plant of claim 14, wherein thelocal solar measurement device is selected from the group consisting ofa solar panel, optical sensor, thermal sensor, radiation sensor andcombinations thereof.
 16. The solar power plant of claim 14, wherein thelocal solar measurement device is a photovoltaic reference cell.
 17. Thesolar power plant of claim 14, wherein the local solar measurementdevice is a weather station configured to measure weather within thesolar power plant and generate local weather data.
 18. The solar powerplant of claim 14, wherein the controller further executes aninstruction to transmit local weather data to an external weatherforecasting service.
 19. The solar power plant of claim 18, wherein thereceived forecast data is from the external weather forecasting service.20. The solar power plant of claim 19, wherein the controller furtherexecutes an instruction to query the external weather forecastingservice to periodically receive the forecast data.